if (classIdx >= details.oneHotNumClasses) {
                        throw new IllegalStateException("Cannot convert sequence writables to one-hot: class index " + classIdx
                                        + " >= numClass (" + details.oneHotNumClasses + "). (Note that classes are zero-" +
                                "indexed, thus only values 0 to nClasses-1 are valid)");
                    }